So I've had the check engine light on for awhile, I decided to get it checked and 4 codes came up....p0102(mass air flow sensor), p0036 (oxygen sensor), p0030 (oxygen sensor circuit), and p0443 (EVAP purg or vent solenoids)....I took it to my mechanic and he got the same codes every time I bought a brand new MAF sensor and it has a brand new o2 sensor as well. The car is a cobalt LT 2007 does anyone know what my issue can be? Maybe the harness for the MAF has a shoartage? The car has an AEM Cold air intake and a zzp downpipe with a catalytic convertor and a magnaflow muffler.